By Max Foster and Chris Liakos, CNN
(CNN) - King Charles III will miss the upcoming COP27 climate change summit in Egypt, CNN understands, after British media reported that Prime Minister Liz Truss advised him to drop his plans to attend.
CNN understands that the King's attendance at COP27 had not been confirmed and following consultations with the government, there was a joint agreement that this would not be the right occasion for Charles's first overseas visit as a sovereign.
CNN has reached out to Buckingham Palace for official comment.
King Charles attended the climate change conference as Prince of Wales in 2021. COP27 is due to take place in Sharm El Sheikh, Egypt in November 2022.
Prince of Wales, Prince William, will also not be attending the climate change summit, according to Kensington Palace.
Charles has been an advocate of environmental causes for at least five decades. He was a prominent backer of the 2015 Paris Climate Accord and discussed the subject with Donald Trump in December 2019, as the then-president prepared to pull the United States out of the pact.
The following month, at the 2020 World Economic Forum in Davos, Switzerland, Charles gave a powerful speech, asking: "Do we want to go down in history as the people who did nothing to bring the world back from the brink in time to restore the balance when we could have done? I don't want to."
Despite criticism -- and at times ridicule -- over his fight to be the royals' ecowarrior, Charles has continued to be a pioneer in green issues in recent years.
Charles was in his element at the COP26 Summit in Glasgow in November 2021, where he implored countries to work with industries to create solutions to climate change.
"We know this will take trillions, not billions, of dollars," he said at the time. Climate change and loss of biodiversity pose a great threat and the world must go on a "war-like footing" to combat them, he added.
US President Joe Biden commented on Charles' decades-long efforts at the event, paying him the ultimate compliment by saying he'd got "the whole thing going" and "that's how it all started."
Charles has been outspoken on a whole range of sensitive issues from genetically modified crops to homeopathic medicines and architecture. It's made him a more divisive figure than his mother, who barely cracked an expression during her reign, let alone expressed an opinion. Elizabeth's legendary ability not to offend and alienate was more strategic than many realize, but Charles has always insisted he intends to follow her lead and stop meddling when he takes the throne.
In 2018, Charles said to the BBC: "The idea, somehow, that I'm going to go on in exactly the same way, if I have to succeed, is complete nonsense because the two -- the two situations -- are completely different." When specifically asked if his campaigning would continue, he said: "No, it won't. I'm not that stupid."
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